Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/OpenAudio_ArduinoLibrary/src/commit/92442b5699b03791afd63d4517b08eb14b888bb0/examples/FineFreqShift_OA
You should set ROOT_URL correctly, otherwise the web may not work correctly.